1. Field of the Invention
This invention relates generally to gelled organic compositions and methods for using the same. In particular, this invention relates to gelled liquid organic fluids, such as gelled liquid hydrocarbons formed from a mixture of an organic-based fluid, a carboxylic acid and/or other hydroxyl-containing compound, and a metal source compound.
2. Description of Related Art
Gelled organic fluids, such as gelled hydrocarbon liquids, may be employed for a variety of different purposes including, but not limited to, applications in the petroleum, refining, chemical and pipeline industries. In one common application, liquid hydrocarbon gels are employed as fluids for stimulation treatment of subterranean formations. Such stimulation treatments include, but are not limited to, hydraulic fracturing treatments with or without proppants, such as sand. In any event, it may be desirable to utilize liquid hydrocarbon gels for the stimulation of subterranean formations which are sensitive or adversely affected by introduction of aqueous-based fluids.
In the past, hydrocarbon liquids have been gelled in a number of different ways. For example, phosphate ester-based hydrocarbon gels are commonly employed in the formulation of hydrocarbon-based well treatment fluids. However, concerns have arisen regarding residual phosphates which may remain in refined petroleum products which have been exposed to, or processed using, phosphate-based hydrocarbon gels (such as through the use of phosphate-containing well treatment fluids, anti-foulants, scale inhibitors, etc.).
Non-phosphate-based hydrocarbon liquid gels have been developed. One conventional non-phosphate method of gelling liquid hydrocarbons involves the saponification of tall oil fatty acids (“TOFAs”) with caustic. However, methods employing this and similar chemistries typically suffer from limited temperature stability, losing effectiveness at temperatures above about 130° F. to about 140° F.
Another conventional method of gelling liquid hydrocarbons involves mixing aluminum salts of long chain fatty acids with liquid hydrocarbons. However, gelation rates of such mixtures is typically very slow at temperatures below about 80° F., requiring heating to obtain satisfactory gelation times.